1. Field of the Invention
The present invention relates to compounds having a vessel smooth muscle relaxation activity, a process for the production thereof, and to the use thereof.
2. Description of the Related Art
Quinoline compounds having a vessel smooth muscle relaxation activity are described in, for example, Japanese Unexamined Patent Publication (KOKAI) Nos. 60-81168, 61-126026, 61-271221, 61-293914, 62-103066, and 63-211267; and U.S. Pat. Nos. 4,456,757, 4,525,589, 4,560,755, 4,634,770, 4,678,783, 4,709,032, and 4,798,897.
Among the compounds described in the above references, some have a satisfactory smooth muscle relaxation activity, but have problems with relation to toxicity, organ-specificity, and safety.